Author: Dr V

IMP: Civilsdaily IAS Prelims 2017 Test Series Module Launched – Click here

• Twelve Questions from science
• Eleven from current affairs
• Ten very doable
• Three questions from space <NASA, MOM, Astrosat>
• One from defence <Astradharini>
• MOM question from way back in 2013

1. With reference to ‘LiFi’, recently in the news, which of the following statements is/are correct?

1. It uses light as the medium for high-speed data transmission.
2. It is a wireless technology and is several time faster than ‘WiFi.

Select the correct answer using the code given below:

(a) 1 only

(b) 2 only

(c) Both 1 and 2

(d) Neither 1 nor 2

• Been in news for last 3 years
• CD newscards
• Common sense
• Wifi wireless fidelity lifi light fidelity
• So light as medium
• Wireless, obviously faster, that’s why developing it

2. In the context of the developments in bioinformatics, the term ‘transcriptome’, sometimes seen in the news, refer to

(a) a range of enzymes used in genome editing

(b) the full range of mRNA molecules expressed by an organism

(c) the description of the mechanism of gene expression

(d)A mechanism of genetic mutation taking place in cells

• Simple biology – transcription is formation of M-RNA from DNA
• Transcript is that m-RNA molecule
• Transcriptome – easily option b

3. ‘Mission Indradhanush’ launched by the Government of India pertains to

(a) Immunization of children and pregnant women

(b) Construction of smart cities across the country

(c) India’ own search for the Earth-like planets in outer space

(d) New Educational policy

• Simple/ newscards/ explains
• Vaccine against 7 dealt diseases

4. ‘Project Loon’, sometimes seen in the news, is related to

a) Waste management technology

b) Wireless communication technology

c) Solar power production technology

d) Water conservation technology

• News card/ explains
• Balloons will reflect broadband signals

5. What is/are unique about ‘Kharai camel’ a breed found in India?

1. It is capable of swimming up to three kilometers in seawater.
2. It survives by grazing on mangrows.
3. It lives in the wild and cannot be domesticated.

Selected the correct answer using the code given below:

(a) 1 and 2 only

(b) 3 only

(c) 1 and 3 only

(d) 1, 2 and 3

• Difficult
• Was in news not so prominently

6. Recently, our scientists have discovered a new and distinct species of banana plant which attains a height of about 11 metres and has orange-coloured fruit pulp. In which part of India has it been discovered?

(a) Anadaman Islands

(b) Anamalai Forests

(c ) Maikala Hills

(d)Tropical rain forest of northeast

• Difficult
• Andaman

7. Which one of the following is the best description of ‘INS Astradharini’, that was in the news recently?

(a) Amphibious warfare ship

(b) Nuclear-powered submarine

(c) Torpedo launch and recovery vessel

(d) Nuclear-powered aircraft carrier

Was in news plus common sense

• Astra dharan karne wali
• Ship holding weapons
• Torpedoes

8. What is ‘Greased Lightning-10 (GL-10)’, recently in the news?

(a) Electric plane tested by NASA

(b) Solar-powered two-seater aircraft designed by Japan

(c) Space observatory launched by China

(d) Reusable rocket designed by ISRO

• In news
• Electric plane by NASA

9. Which of the following statements is/are correct?

Viruses can infect

1. Bacteria
2. Fungi
3. Plants

Select the correct answer using the code given below:

(a) 1 and 2 only

(b) 3 only

(c) 1 and 3 only

(d) 1, 2 and 3

• Obvious. Can infect every organism
• Bacteriophage, plant and fungus everyone knows

10. India is an important member of the ‘International Thermonuclear Experimental Reactor’. If this experiment succeeds, what is the immediate advantage for India?

(a)    It can use thorium in place of uranium for power generation

(b)    It can attain a global role in satellite navigation

(c)    It can drastically improve the efficiency of its fission reactors in power generation

(d)    It can build fusion reactors for power generation

• Thermonuclear bomb – hydrogen bomb (think north korea)
• Hydrogen bomb fusion
• Answer fusion reactors

11. With reference to ‘Astrosat’, the astronomical observatory launched by India, which of the following statements is/are correct?

1.    Other than USA and Russia, India is the only country to have launched a similar observatory into space.
2.    Astrosat is a 2000 kg satellite placed in an orbit at 1650 km above the surface of the Earth.

Select the correct answer using the code given below

1. a)    1 only
2. b)    2 Only
3. c)    Both 1 and 2
4. d)    Neither 1 nor 2

• Apart from USA and Russia, India only country
• What about EU??
• False
• 2000 kg
• PSLV can’t launch very heavy satellites <can launch only upto 1650 kg>

12  Consider the following statements:

The Mangalyaan launched by ISRO

1.    is also called the Mars Orbiter Mission
2.    Made India the second country to have a spacecraft orbit the Mars after USA
3.    Made India the only country to be successful in making its spacecraft orbits the Mars in its very first attempt.

Which of the statements given above is/are correct?

(a)    1 only

(b)    2 and 3 only

(c)    1 and 3 only

(d)    1, 2 and 3

• 2nd only red flag# incorrect
• 3rd also has red flag but it’s true. Was so much in news

1. To meet its rapidly growing energy demand, some opine that India should pursue research and development on Thorium as the future fuel of nuclear energy. In this context, what advantage does Thorium hold over uranium?

• 1. Thorium is far more abundant in nature than uranium
• 2. On the basis of per unit mass of mined mineral, thorium can generate more energy compared to natural uranium.
• 3. Thorium produces less harmful waste in comparison to uranium.

Which of the statements given above is/are Correct?

• [A]1 Only
• [B]2 & 3 Only
• [C]1 & 3 Only
• [D]1,2 & 3
• 1 is true everyone knows that <monazite sands>
• 3rd is also true, No risk of proliferation with thorium
• 2nd is also true as it is wrt per unit mass of mined mineral <4times more energy>

2. Graphene is frequently in news recently. What is its importance?

• 1. It is a two-dimensional material and has good electrical conductivity.
• 2. It is one of the thinnest but strongest materials tested so far.
• 3. It is entirely made of silicon and has high optical transparency.
• 4. It can be used as ‘conducting electrodes’ required for touch screens, LeOs and organic LEOs.

Which of the statements given above are correct?

• [A]1 and 2 only
• [B]3 and 4 only
• [C]1, 2 and 4 only
• [D]1,2,3 & 4
• Graphene is carbon not silicon
• eliminate 2
• Others all true, Nobel prize was awarded for graphene that time

3. Lead, ingested or inhaled, is a health hazard. After the addition of lead to petrol has been banned, what still are the sources of lead poisoning?

• 1. Smelting units
• 2. Pens and pencils
• 3. Paints
• 4. Hair oils and cosmetics

Select the correct answer using the codes given below:

• [A]1,2 & 3 only
• [B]1 and 3 only
• [C]2 & 4 only
• [D]1,2,3 & 4
• Lead in pencils and pens seriously!
• Don’t get fooled by term lead pencil
• Eliminate 2, reach the answer

4. With reference to ‘stem cells’ frequently in the news, which of the following statements is / are correct?

• 1. Stem cells can be derived from mammals only
• 2. Stem cells can be used for screening new drugs.
• 3. Stem cells can be used for medical therapies.

Select the correct answer using the codes given below:

• [A]1 & 2 Only
• [B]2 & 3 Only
• [C]3 Only
• [D]1,2 and 3
• 1st statement, only, read flag, pause and think.
• What’s wrong with birds or other animals and plants?
• Obviously wrong
• Eliminate 1
• 2 is true, drug testing on cells, make tissue from stem cells and test drugs

5. Recently, there has been a concern over the short supply of a group of elements called ‘rare earth metals’. Why?

• 1. China, which is the largest producer of these elements, has imposed some restrictions on their export.
• 2. Other than China, Australia, Canada and Chile, these elements are not found in any country.
• 3. Rare earth metals are essential for the manufacture of various kinds of electronic items and there is a growing demand for these elements.

Which of the statements given above is/are correct?

• [A]1 Only
• [B]2 & 3 Only
• [C]1 & 3 Only
• [D]1,2 & 3
• 2nd not found in any other country, not even an ounce. It’s not possible, Rare earth is found in India also
• 3rd is true, electronics etc
• eliminate 2, include 3

6. A team of scientists at Brookhaven National Laboratory including those from India created the heaviest anti-matter (anti-helium nucleus). What is/are the implication/ implications of the creation of anti-matter?

• 1. It will make mineral prospecting and oil exploration easier and cheaper.
• 2. It will help probe the possibility of the existence of stars and galaxies made of anti-matter.
• 3. It will help understand the evolution of the universe.

Select the correct answer using the codes given below :

[A]1 Only

[B]2 & 3 only

[C]3 Only

[D]1,2 & 3

• This matter/ anti matter things is of quantum physics , to know about universe so 1st statement mineral prospecting and all is incorrect
• 2 and 3 are true by the same logic

7. Electrically charged particles from space travelling at speeds of several hundred km/sec can severely harm living beings if they reach the surface of the Earth. What prevents them from reaching the surface of the Earth?

• [A]The Earth’s magnetic field diverts them towards its poles
• [B]Ozone layer around the Earth reflects them back to outer space
• [C]Moisture in the upper layers of atmosphere prevents them from reaching the surface of the Earth[D]None of the statements (a), (b) and (e) given above is correct

• See similar question asked this year in CAPF about magnetic lines converging at the poles
• So diverted at the pole
• That’s why auroae

8. Consider the following statements If there were no phenomenon of capillarity

1. it would be difficult to use a kerosene lamp

2. one would not be able to use a straw to consume a soft drink

3. the blotting paper would fail to function

4. the big trees that we see around would not have grown on the Earth

Which of the statements given above are correct?

[A]1, 2 and 3 only

[B]1, 3 and 4 only

[C]2 and 4 only

[D]1, 2, 3 & 4

• While using straw, we consume our own energy, we suck fluid, no use of capillary action
• Eliminate option 2

1. That completes your science tech. I think you are good to go now.
2. Go there express yourself.
3. Sorry for not being able to complete art and culture part
4. Do login the morning for a useless article about last day and exam hall plan

Pre 2014

1. Which of the following is/are the example/examples of chemical change?

1. Crystallization of sodium chloride
2. Melting of ice
3. Souring of milk

Select the correct answer using the code given below.

1. 1 and 2 only
2. 3 only
3. 1, 2 and 3
4. None

• 1 is crystallisation, so only physical form is changing not chemical
• Same with melting of ice h20 remains h20
• Souring of milk, chemical Composition changes as there’s acidification

2. Consider the following diseases

1. Diphtheria
2. Chickenpox
3. Smallpox

Which of the above diseases has/have been eradicated in India?

1. 1 and 2 only
2. 3 only
3. 1, 2 and 3
4. None

• Small pox everyone knows
• Chickenpox is an innocuous disease. Many of you may have contacted chicken pox during childhood
• Diphtheria vaccine aaj bhi DPT. Don’t say polio has been eradicated but uski vaccine bhi so funda bekar

3. Consider the following pairs :

Which of the pairs given above is/are correctly matched?

1. 1 and 2 only
2. 3 only
3. 1, 2 and 3
4. None

• 7th std science
• Vitamin A – night blindness
• C – scurvy
• D – rickets
• B1 – vetiver
• b3 – niacin – pallegra

4. In addition to fingerprint scanning, which of the following can be used in the biometric identification of a person?

1. Iris scanning
2. Retinal scanning
3. Voice recognition

Select the correct answer using the code given below.

1. 1 only
2. 2 and 3 only
3. 1 and 3 only
4. 1, 2 and 3

• Common sense
• All are unique. All can be used

5. Which of the following pair is/are correctly matched?

Select the correct answer using the code given below.

1. 1 only
2. 2 and 3 only
3. 1 and 3 only
4. 1, 2 and 3

• Cassini – Saturn very famous
• Learn about recent missions of NASA and ISRO

Pre 2013

1. Which of the following diseases can be transmitted from one person to another through tattooing?

1. Chikungunya
2. Hepatitis B
3. HIV-AIDS

Select the correct answer using the codes given below.

1. 1 only
2. 2 and 3 only
3. 1 and 3 only
4. 1, 2 and 3

• Tattooing ie disease due to needle I. E blood
• Chikungunya we know is due to mosquito bite
• Eliminate it and reach the answer
• Hepatitis b and hiv are due to blood transfusion among other things

2. Consider the following minerals

1. Calcium
2. Iron
3. Sodium

Which of the minerals given above is/are required by human body for the contraction of muscles?

1. 1 only
2. 2 and 3 only
3. 1 and 3 only
4. 1, 2 and 3

• Calcium is necessary for muscle contraction
• Sodium for transmission of impulse

3. Which of the following statements is / are correct?

1. Viruses lack enzymes necessary for the generation of energy.
2. Viruses can be cultured in any synthetic medium.
3. Viruses are transmitted from one organism to another by biological vectors only.

Select the correct answer using the codes given below.

1. 1 only
2. 2 and 3 only
3. 1 and 3 only
4. 1, 2 and 3

• 2 is incorrect. Virus can not be cultured in any synthetic medium. Any is red flag.
• Similarly only is red flag in statement 3. Pause and think of other vectors

4. Recombinant DNA technology (Genetic Engineering) allows genes to be transferred

1. across different species of plants
2. from animals to plants
3. from microorganisms to higher organisms

Select the correct answer using the codes given below.

1. 1 only
2. 2 and 3 only
3. 1 and 3 only
4. 1, 2 and 3

• Simple
• Can be transferred from anywhere to anywhere

5. Improper handling and storage of cereal grains and oilseeds result in the production of toxins known as aflatoxins which are not generally destroyed by normal cooking process. Aflatoxins are produced by

1. bacteria
2. protozoa
3. moulds
4. viruses

Fungus/ mould. Aspergillus Flavis

6  Fruits stored in a cold chamber exhibit longer storage life because

1. exposure to sunlight is prevented
2. concentration dioxide in the is increased of carbon environment
3. rate of respiration is decreased
4. there is an increase in humidity

• For longer shelf life, metabolic rate is to be reduced
• Decreased rate of respiration helps in that
• Increase humidity, high co2, exposure to sunlight is crap. It can be achieved in other ways also without needing cold chamber

7. Many transplanted seedlings do not grow because

1. the new soil does not contain favorable minerals
2. most of the root hairs grip the new soil too hard
3. most of the root hairs are lost during transplantation
4. leaves get damaged during transplantation

• 1 is crap. We can artificially add minerals to the new soil. It has to be about transplanted plant
• 2nd – why would it occur? No idea
• 3rd is very plausible. And loss of root hairs will prevent growth

8. Which of the following leaf modifications occurs/occur in desert areas to inhibit water loss?

1. Hard and waxy leaves
2. Tiny leaves or no leaves
3. Thorns instead of leaves

Select the correct answer using the codes given below.

1. 1 and 2 only
2. 2 only
3. 1 and 3 only
4. 1, 2 and 3

NCERT ecological portion or common sense

9. Ball bearings are used in bicycles, cars, etc.because

1. The actual area of contact between the wheel and axle is increased
2. The effective area of contact between the wheel and axle is increased
3. The effective area of contact between the wheel and axle is reduced
4. None of the statements is correct

• It is to reduce friction
• Less effective area of contact, less friction force
• In any case b and c are contradictory, one has to be true unless you think it has no relations with effective area

10. Consider the following phenomena:

1. Size of the sun at dusk
2. Colour of the sun at dawn
3. Moon being visible at dawn
4. Twinkle of stars in the sky
5. Polestar being visible in the sky

Which of the above are optical illusions?

1. 1, 2 and 3
2. 3, 4 and 5
3. 1, 2 and 4
4. 2, 3 and 5

• Polestar we all know is for real and not am optical illusion.
• Eliminate 5
• We also know stars are like sun. As the Sun doesn’t twinkle, stars also should not but they do. That’s optical illusion

11. Rainbow is produced when sunlight falls on drops of rain.

Which of the following physical phenomena are responsible for this?

1. Dispersion
2. Refraction
3. Internal reflection

Select the correct answer using the codes given below.

1. 1 and 2 only
2. 2 and 3 only
3. 1 and 3 only
4. 1, 2 and 3

9th std physics

Water droplets act as prisms, refract and disperse the light, light is then reflected internally (total internal reflection) and then refract again while coming out of raindrops.

12. The known forces of nature can be divided into four classes, viz, gravity, electromagnetism, weak nuclear force and strong nuclear force. with reference to them, which one of the following statements is not correct?

1. Gravity is the strongest of the four
2. Electromagnetism act only on particles with an electric charge
3. Weak nuclear force causes radioactivity
4. Strong nuclear force holds protons and nutrons inside the nuclear of an atom.

• Gravitational force is the weakest so 1st is untrue
• Regarding 2nd. Only red flag. Pause and think. Does it act Only on charged particles? I am not sure ?
• Strong nuclear the strongest

13. The efforts to detect the existence of Higgs boson particle have become frequent news in the recent past. What is /are the importance/importance of discovering this particle?

1. It will enable us to understand as to why elementary particles have mass.
2. It will enables us in the near future to develop the technology to transferring matter from one point to another without traversing the physical space between them.
3. It will enable us to create better fuels for nuclear fission.

Select the correct answer using the codes given below:

1. 1 only
2. 2 and 3 only
3. 1 and 3 only
4. 1, 2 and 3

• Was very much in news
• 1st is easily true.
• 3rd is false. How can it create better fuel for fission?

Science and technology portion constitutes an important part of CSE prelims.

Weightage of science and technology

• 2015 – 9
• 2014 – 5
• 2013 -13
• 2012 – 9
• 2011 – 18

But the syllabus is vast and standard thing of reading NCERT books does not apply here as it’s very difficult for non science background people to learn NCERT physics, chemistry, biology 12th std. UPSC also does not ask questions of 11th 12th standard and if any such question is asked, don’t even try to attempt that question.

• Having said that, 6th to 8th std NCERT remains important to clear basic concepts or you can just skim through the general science notes of any coaching classes.
• Use your logic to the full for science is nothing if not logical.
• Technology questions are primarily current affairs based and do not require in depth understanding.

Things to be done in these last 2 days

• Just go through science and technology current affairs from June to February
• Go through previous year questions

IAS Pre 2015

1. With reference to the use of nanotechnology in health sector, which of the following statements is/are correct?

1. Targeted drug delivery is made possible by nanotechnology
2. Nanotechnology can largely contribute to gene therapy

Select the correct answer using the code given below.

(a) 1 only

(b) 2 only

(c) Both 1 and 2

(d) Neither 1 nor 2

• Both the statements seem true
• There is no good reason for any of them to be untrue.
• Targeted drug delivery i.e delivering drug to the site of action not to all organs by some how nano tagging the drug
• Gene therapy again by somehow nano tagging the gene
• 2. With reference to ‘fly ash’ produced by the power plants using the coal as fuel, which of the following statements is/are correct?

1. Fly ash can be used in the production of bricks for building construction
2. Fly ash can be used as a replacement for some of the Portland cement contents of concrete
3. Fly ash is made up of silicon dioxide and calcium oxide only, and does not contain any toxic elements.

Select the correct answer using the code given below

(a) 1 and 2

(b) 2 only

(c) 1 and 3

(d) 3 only

We have done this in environment section

3. Among the following which were frequently mentioned in the news for the outbreak of Ebola virus recently?

(a) Syria and Jordan

(b) Guinea, Sierra Leone and Liberia

(c) Philippines and Papua New Guinea

(d) Jamaica, Haiti and Surinam

Was very much in news

• Even if you only knew that it affected Africa which I suppose everyone knows, you would be good to go.
• Jordan, Syria in Asia
• Jamaica, Haiti in Caribbean
• Philippines Asia
• You see, the stupid examiner is trying to play with words. Syria sierra, Guinea papua new guinea etc

4. In the context of modern scientific research, consider the following statements about ‘IceCube’, a particle detector located at South Pole, which was recently in the news :

1. It is the world’s largest neutrino detector, encompassing a cubic kilometre of ice.
2. It is a powerful telescope to search for dark matter
3. It is buried deep in the ice.

Which of the statements given above is/are correct?

(a) 1 only

(b) 2 and 3 only

(c) 1 and 3 only

(d) 1,2 and 3 only

• Current affairs, was in news
• If you know about neutrino, Indian neutrino observatory, you would know they are set up at places where there is minimum disturbance like deep inside earth
• Now it’s ice cube so a and c seem right
• Neutrino search and understanding of dark natter is realted
• Anyway you should have read the news and no need for these useless tikdams

5. With reference to ‘Near Field Communication (NFC) Technology’, which of the following statements is/are correct?

1. It is a contactless communication technology that uses electromagnetic radio fields
2. NFC is designed for use by devices which can be at a distance of even a metre from each other
3. NFC can use encryption when sending sensitive information.

Select the correct answer using the code given below.

(a) 1 and 2 only

(b) 3 only

(c) 1 and 3 only

(d) 1,2 and 3

• Near field so would obviously be contactless. You must have seen this during billing in  grocery stores
• Even a meter meaning long distance, it’s near field so untrue statement.
• 3rd has to be true. it’s such an innocuous statement.
• In any case include 1, exclude 2, reach the answer

6. The term ‘Goldilocks Zone’ is often seen in the news in the context of

(a) the limits of habitable zone above the surface of the Earth

(b) regions inside the Earth-like planets in outer space

(c) search for the Earth-like planets in outer space

(d) search for meteorites containing precious metals

• Was in the news related to exoplanets
• 1st is rubbish
• 4th is also rubbish
• B/w 2 and  you can be confused
• But 2nd – what regions inside earth like planets would be goldilock?
• 3rd is true as earth like planets which are presents in zones called goldilock can be habitable

7. The term ‘IndARC’ sometimes seen in the news, is the name of?

(a) an indigenously developed radar system inducted into Indian Defence

(b) India’s satellite to provide services to the countries of Indian Ocean Rim

(c) a scientific establishment set up by India in Antarctic region

(d) India’s underwater observatory to scientifically study the Arctic region

• Current affairs
• CD newscards
• Or common sense. IndARC – India arctic

8. H1N1 virus is sometimes mentioned in the news with reference to which one of the following diseases?

(a) AIDS

(b) Bird flu

(c) Dengue

(d) swine flu

• Was in news, many death in Delhi in the month of Feb, March
• AIDS virus you know is HIV.
• Dengue you know is dengue virus
• Bird flu is h5n1
• Swine flu h1n1

9. With reference to bio-toilets used by the Indian Railways, consider the following statements:

1.The decomposition of human waste in the bio-toilets is initiated by a fungal inoculum.

2. Ammonia and water vapour are the only end products in this decomposition which are released into the atmosphere.

Which of the statements given above is/are correct?

(a) 1 only

(b) 2 only

(c) Both 1 and 2

(d) Neither 1 nor 2

• Covered in environment section
• Not by fungi but bacteria
• Why only ammonia and water vapour, what about other gases?

10. With reference to ‘fuel cells’ in which hydrogen-rich fuel and oxygen are used to generate electricity. Consider the following statements:

1. If pure hydrogen is used as a fuel, the fuel cell emits heat and water as by-products.
2. Fuel cells can be used for powering buildings and not for small devices like laptop computers.
3. Fuel cells produce electricity in the form of Alternating Current (AC).

Which of the statements given above is / are correct?

(a) 1 only

(b) 2 and 3 only

(c) 1 and 3 only

(d) 1, 2 and 3

• Covered in environment section
• Cells produce dc not AC

This is solution of CAPF science portion, You need not worry about difficult physics questions as they won’t be asked in civil services examination. Just focus on how to solve with limited knowldge

1. Which of the following statements is correct?
1. Gravitational waves were predicted by Albert Einstein in 1916 on the basis of his theory of General Relativity
2. Gravitational waves do also exist in the Newtonian theory of Gravitation
3. Gravitational Waves are to be detected by very sensitive detectors known as Interferometes
Select the correct answer using the code given below:
(a) 1only
(b) 1 and 3 only
(c) 2 and 3 only
(d) 1, 2 and 3

• Very much in news
• CD newscards and explainers cover everything
• In any case, 2nd statement is false as quantum physics is not in Newtonian mechanics

2. Who among the following scientists of Indian origin is / has been the President of Royal Society?

(a) Ronald Ross
(b) Har Gobind Khorana
(c) Chandrasekhara Venkata Ramana
(d) Venkataraman Ramakrishnan

• Useless question
• Not doable

3. A change of state directly from solid to gas without changing into liquid state is called:

(a) Fusion
(b) Sublimation
(c) Diffusion
(d) Emulsion

• 5th standard science
• Eg. camphor

4. Water at 273 K is less effective in cooling than ice at the same temperature. It is because :

(a) water is difficult to handle
(b) water at 273 K has less energy than ice at the same temperature
(c) water at 273 K has more energy than ice at the same temperature
(d) water is not a cooling agent

• Common sense
• Cooling means energy should be transferred to coolant. Less energy means more energy could be transferred hence more coiling
• Easily the c
• In any case b and c are contradictory, one has to be true

5. Which one of the following is not a colloid?

(a) Milk
(b) Mud
(c) Butter
(d) Boric acid

• Even if you don’t know anything, you can easily spot odd one out
• Crystals form pure solution while colloids don’t
• Milk, mud, butter easily colloid

6. Which one of the following statements is not correct?

(a) Bleaching powder is prepared by the action of Chlorine on dry slaked lime [Ca(OH)2]
(b) Bleaching powder acts as a reducing agent in many chemical industries
(c) Bleaching powder is also known as chlorinated lime
(d) Bleaching powder is used for disinfecting drinking water

• Bleach – Ca(OH)2 . is oxidizing agent
• All fashion conscious people know this
• Even if you don’t know this, it can not act as reducing agent, it gives oxygen hence oxidizing

7. Which one of the following statements is not correct?
(a) Graphite is a non-metal
(b) Graphite is an allotrope of carbon
(c) Graphite is a conductor of electricity
(d) Graphite has a tetrahedral structure

• Graphite is carbon, allotrope, non metal, 1 and 2 easily true
• Conductor of electricity – reason for its widespread use
• It’s hexagonal – 6th std science
• So many questions have been asked on Graphite and graphene

8. Consider the following physical quantities: Energy , power, pressure, impulse, temperature, gravitational potential
Which of the above is / are the vector quantity / quantities ?
(a) Impulse only
(b) Impulse and pressure only
(c) Impulse , temperature and pressure
(d) Gravitational potential

• 9th std science
• Temperature can not be vector
• Vector is associated with a specific direction like velocity, force
• Pressure is in all directions not a vector
• Impulse is
• Though it’s given in class 11 NCERT, you don’t need to read that

9. A piece of stone tied to a string is made to revolve in a circular orbit of radius r with other end of the string as the centre. If the string breaks, the stone will:
(a) move away from the centre
(b) move towards the centre
(c) move along a tangent
(d) stop

• Newtonian laws of motion
• Inertia principle <will move in the initial direction>
• You would have observed this
• Again 9-10th std physics

10. Which one of the following statements is not true?

(a) The gravitational force of earth acting on a body of mass 1 kg is 9.8 newton
(b) The force acting on an object of mass 5 kg moving with a uniform velocity of 10 m/s on a frictionless surface is zero
(c) The SI unit of weight is kg
(d) The momentum of a man having mass 100 kg walking with a uniform velocity of 2 m/s is 200 newton second

• Kg is unit of mass
• Weight is force so unit would be newton

11. Which one of the following statements is correct?

(a) Acceleration due to gravity decreases with the increase of altitude
(b) Acceleration due to gravity increases with the increase of depth [assuming earth to be a sphere of uniform density]
(c) Acceleration due to gravity decreases with the increase of latitude
(d) Acceleration due to gravity is independent of the mass of the Earth

• Easy peasy 1st option
• You move away from a body, gravitational force would decrease
• Increase in altitude, away from earth. Don’t worry about other options
• But now learn them too

12. A Barometer kept in an elevator reads 760 mm when the elevator is at rest. When the elevator moves in the upward direction with increasing speed, the reading of the Barometer will be :
(a) 760 mm
(b) < 760 mm
(c) > 760 mm
(d) Zero

• Difficult question
• Don’t think too much
• You can apply your effective weight of m(g+a) to solve the problem

13. Which one of the following statements is not correct?

(a) The earth’s magnetic field is due to the motion of metals like iron and nickel in the core of the earth
(b) The magnetic field lines of force are widely separated near the poles of a magnet but these lines come closer to one another at other places
(c) If the cross sectional area of a magnetic field increases, but the flux remains the same, the flux density decreases
(d) When the speed of a conductor moving through a magnetic field is increases, the included voltage increases

• You would have seen the images
• Magnetic lines converge at the poles

14. Let a resistor having 4 ohm resistance be connected across the terminals of a 12 volt battery. Then the charge in coulomb passing through the resistor per second is :
(a) 12
(b) 4
(c) 3
(d) 0.33

• V = IR
• Current would be 3

15. Arrange the following substances in their order of increasing hardness:
1. Gypsum
2. Topaz
3. Fluorite
4. Feldspar
Select the correct answer using the code given below:
(a) 4-3-2-1
(b) 1-3-4-2
(c) 3-4-2-1
(d) 1-4-3-2

• NCERT physical geography
• Gysum would be the softest so you could easily eliminate 2 options

P.S. – Solutions of CSE pre 2013, 2014 ad 2015 with brief analysis will be at your desk by midnight

P.P.S. – Don’t be scared of science and technology